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F. I. DU PONT. REMOVAL 0F ACIDS PROM NITROGELLULOSE AND 0E NTRIFUGAL MACHINE THEREFOR. APPLICATION FILED APR.14, 1909.

MM, 7' UFA/.EE

W/ T/VESSES.' M1.

E. I. DU PONT. REMOVAL OP ACIDS PRUM NITROGELLULOSE AND GENTRIPUGAL MACHINE THEREPGR. APPLICATION FILED PE.14,1909.

1,024,624 Patented Ap1 -.30,'1912.

2 SHEETS-SHEET 2.

'TORIVE V.

4 To all whom it may concern:

UNITED sTATEs PATENT oEEI-CE. i

FRANCIS I. nu PONT, or WILMINGTON, DELAWARE,l AssIeNon To THE E. I. nu PONT ma NEMOURS POWDER COMPANY, 01E WILMINGTON, DELAWARE, A GOEPORTION QF NEW JERSEY.

REMOVAL or ACIDS FROM NITRooELLULosE AND cENTRIrU-GAL MACHINE THEREFQE,

Be it lmown that I, FRANCIS- DU PONT, a citizen of the United States, and a resident of Wilmington, in the county of Newcastle and State of Delaware, have invented certain new and useful Improvements in the Removal of Acids from Nitrocellulose and .in Centrifugal Machines Therefor, of which t-he following is a speciiication.

Objects of the invention are, first, to provide an efficient and reliable. continuous Working centrifugal machine, or more specically stated, to provide a centrifugal machine for continuously separating acid from` gun cotton; second, to effect a saving of labor and to insure a constant efiiciency of ,operation in the separation of acid and gun cotton, third, to provide eflicient means for continuously feeding in a proper manner the material through the centrifugal machine, and fourth, to provide simple mechanism of which the` gears move relatively slowly for driving the parts of the centrifugal machine at high speed, yet with the necessary relative difference of speed between them.

To these and other ends hereinafter set forth the invention comprises the continuous Working centrifugal machine, as well as certain other improvements to be presy.'

ently described and nally claimed.

In the following description, reference will be made to the type of embodiment of the invention chosen for illustration in the accompanying illustrative drawings form- ,ing part hereof, and in which- Figure 1, is a side elevation, partly in section, of a continuous working centrifugal machine embodying features of the in-` vention. Fig. 2, is a transverse sectional view taken on the line 2-,2 of Fig. 1, looking toward the leftand Fig. 3, is a view principally in central section, drawn to an enlarged scale, and illustrating the driving mechanism shownv at the left-hand side in Fig. 1.

In the drawings 1, is a stationary cylinder or housing surrounding or inclosig a-'cylinder 2, ,arranged for rotation about a horizontal axis. The curved Wall of the cylinder 2, is perforated and the ends of the cylinder 2 consist, generally speaking,v of spiders 3 and 4, although the spider 4 carries a head 5, which is connected with the Specification of Letters Patent.

curved wall of the cylinder. The shaft 6 is revoluble in the sleeve 7, and it is connected with the spider 4 and with an intake or feed tube 8. The shaft 6 has appropriate bearings, shown at 9 as of the roller variety, within the sleeve 7 and the tube 8 has appropriate bearings, also shown as of the roller variety at 10, within the pedestal or support 11,. The spider 3, is revoluble in respect to the sleeve 7 and as shown roller bearings 12,

are interposed between the two. Thus when the shaft 6 is turned it causes the perforated cylinder 2 to revolve about a horizontal axis.

The sleeve 7 carries slanting blades or feeders 13, arrangedat an inclination to the axis ofthe cylinder 2 and disposed so as to cooperate with its perforated wall. These slanting blades 0r feeders 13 are shown as attached to a cage 14, the radial arms of which are connected with the sleeve, 7 and 'the longitudinal arms of which carry the slanting blades or feeders 13. The stationary cylinder or housing 1 is provided with an inclined bottom which communicates with an offtake 15 and it may be said to be internally divided as by the partition 16, so as to form a chamber 17 at its outlet end, which chamber 17 communicates with lan oftake 18.

19, is a feed screw which,`when present, may be driven by means of the pulley 20.,

21, is a stationary hopper which communicates with the intake or feed tube 8. Provisions are shown at 22, in the nature of a gland or stung box, which enable the tube 8 to rotate in respect to the part 21.` .The shaft 6 and the sleeve 7 are driven at a high speed, for example, the shaft may run at six hundred revolutions per minute and the sleeve is driven at a high speed ybut, somewhat -more slowly thanl the cylinder 2, for example, the speed of the sleeve may be Patented Apr. 30, 1912. Application led April 14, 1909. Serial No. 489,773. i

ten or twelve revolutions per minute less.-

pulley or drum intended to b-e driven by a suitable belt or the like, and it is revolubly supported by means of the pedestals 2-l and 25, or perhaps more accurately, by means of parts carried by these pedestals. Within the pulley there is a gear 26 fast to a spud 27 held by the pedestal 24, so that the gear 26 is fixed. Rotatably mounted within the drum, as on the shaft 28 carried thereby, is an internally toothed wheel 29 meshing with the gear 26. Connected with the internal gear 29, for example, fast upon the shaft 28, are gear wheels 30 and 3l. rlhe gear wheel 80 meshes with a gear wheel 32 fast to the shaft 6 and the gear wheel 3l meshes with a gear wheel 33 fast to the sleeve 7 'llhe rela tive number of teeth on the intermeshing gear wheels 30 and 32, and the intermeshing gear wheels 3l and 33, is such that the shaft 6 and the sleeve 7 are driven at the required speed and at the required differencein speed. The described mechanical or differential device is possessed of advantages and among which it may be pointed outI that the gears relative to each other are slow running gears and yet their effect is to materially increase the speed from the driver to the driven parts. It may be said that the described roller bearings are advantageous because they are arranged in locations where proper lubrication of ordinary bearings would be diiiicult;

The mode of operation of the described continuous working centrifugal machine will be explained in connection with the separation of gun cotton from acid', but its use is not to be thereby unduly limited.

Gun cotton and acid are continuously fed through the hopper 21 and tube`8, through the spaces between the arms of the spider 4 into the interior of the rapidly rotating perforated cylinder 2. In some instances this material may continuously flow through ,the described passages, but if it does not flow properly use may be made of the feed screw 19, which, when present, mayadvantageously be revolved somewhat slower than the intake or tube 8. The material being thus continually fed into the perforated cylinder 2, which is rapidly rotatingnabout a horizontal axis, is subjected to centrifugal action, the acid passing through the perforated wall of the cylinder and escaping into the casing l and thence by the offt-ake l5, and the gun cotton remaining in theperforated cylinder. As the gun cotton is thus freed from acid, it is fed through the horizontally rotating cylinder 2 and escapes at the left-hand end thereof, past the arms of the spider 3 into the chamber 17 and thence by way of the offtake 18. The feed of the material through the rapidly rotating horizontal cylinder is accurately controlled and properly governed by the speed of the slantng blades or feeders 13, which, as has been inattesa said, rotate rapidly yet somewhat more slowly than the perforated cylinder and this difference inspeed between the perforated cylinder and the feeders is important, since it brings about an appropriate yet contin- `uous feed for giving` rise to a continuous stream of acids and a continuous stream of gun cotton. Stufling boxes or glands 34 are shown as applied between the ends of the housing or casing and the intake tube 8 and the sleeve 7. They serve to prevent leakage at these points of both liquid and air so that air is excluded from the casing. According to my invention the nitro-cellulose when subjected to this process is maintained out of contact with the air so that the nitro cellulose as well as the apparatus itself are prevented from undergoing such chemical changes as are due to moisture in the atmosphere. The point is thatbetter results are attained by the removal of acids from nitro-cellulose when the air of the atmosphere is excluded because the moisture in the atmosphere may be and is likely to bring about `undesirable chemical changes.

`What I claim is:

l. ln a centrifugal machine the combination of a horizontal cylinder carrying shaft, a feeder carrying sleeve mounted thereon. a revoluble drum or pulley concentric with said sleeve and shaft, a fixed gear wheel concentric with said pulley or drum, an internally toothed wheel revolubly carried by said pulley or drum and meshing with said fixed gear wheel, and intermeshing gear wheels interposed betweensaid internal gear wheel and said shaft and sleeve and provided with the requisite number of teeth for imparti the required differential speed to said shflt and sleeve, substantially as described. t

2. A continuous working centrifugal machine comprising the combination of a horizont-al shaft provided with a spider and with an imperforate cylinder head and with an intake tube, a pedestal in which said tube is revoluble, a sleeve revolubly mounted on said` shaft, a pedestal in which said sleeve is revoluble, a perforated cylinder carried by said head and having a spider revoluble on said sleeve, scraper blades carried by said sleeve and arranged for cooperation with the interior of the curved wall of the cylinder and arranged at an inclination 'to the aXis thereof, a revoluble pul- 'ley or drum concentric withthe axis of thel sleeve and shaft, a pedestal carrying a Spud on which said pulley is revoluble and which is provided with a fixed gear wheel, an internal toothed wheel revolubly mounted on the pulley or drum and meshing with said fixed gear, and intermeshing gear wheels interposed between the ydrum and said shaft and said sleevey and having the requisite diierence in number of teeth for producing the required differential speed of said sleeve and shaft, substantially vas ldescribed.

3. A continuous Working centrifugal machine comprising the combination of a horizontal shaft provided with a spider and with an imperforate cylinder head' and with an intake tube, alpedestal in which said tube is revoluble, a sleeve revolubly mounted on said shaft, roller bearings interposed be-v tween the shaft and sleeve, a pedestal in which said sleeve is revoluble, a perforated cylinder carried by said head and having a spider revoluble on said sleeve, a roller bearing interposed between the spider and sleeve, scraper blades carried by said sleeve and arranged for coperatie-n with the interior of the curved wall ofthe cylinder and arranged at an inclination to the axis thereof, a revoluble pulley or drum concentric with the axis of the sleeve and shaft, a

pedestal carrying a spud on which said pul.

ley is revoluble and which is provided with a fixed gear wheel, an internal toothed wheel revolubly mounted on the pulley or drum and meshing with said fixed gear, and intermeshing gear wheels interposed between the drum and said shaft and said sleeve and having the requisite difference in number of'teeth for producing the required differential speed of said sleeve and shaft, substantially as described.

4. In apparatus for the removal of acids from nitrocellulose the combination of a perforated cylinder rotatable 'at a high enough velocity to produce centrifugal force, a conveyer adapted to move the solid material longitudinally through this cylinder moving ata velocity differing but slightly from thevelocity of the cylmder so that with reference to the cylinder the conveyer moves slowly, and an inclosing casing which prevents moisture of the atmosphere from affecting the materials 'in the apparatus, substantially as described. i

5. Apparatus for the removal of acids from nitrocellulose which comprises the combination of a perforated centrifugal drier, a conveyer running relatively slowly in respect to the surface of the drier for passing the nitrocellulose through .the centrifugal drier, and means for maintaining the Whole out of contact with the atmosphere, substantially as described.

In testimony whereof -I havehereunto signed my name.

FRANCIS I. DU PONT.

Witnesses:

GORDON L. -NAYL0R,' J. ED. WILSON. 

